The objectives of this project are to enroll children with cancer in clinical trials, to develop clinical trials and study the biologic behaviors of childhood cancer, and to improve and evaluate the disease- free survival of patients enrolled in these clinical trials. In order to achieve these goals, the member institutions of the Pediatric Oncology Group (POG) meet biannually to discuss, develop, and implement clinical trials for the most common childhood malignancies and to supply the reference research laboratories of the proper material or tissue necessary for the research. Since 1989, CMH has been one of the member institutions of POG who is actually involved in the accrual of children with cancer to clinical trials. CMH's faculty is also involved in the coordination of studies either as the Principal Investigator or co-Investigator. These protocols are POG 9443, POG 9240/41/42, POG 9135/6, POG 9410, NTWS #5. Participation in administrative activities within POG include the POG Chairperson, the POG Executive Officer, the Head of the Neuroblastoma Biology Committee, the Head of the Neuroblastoma Bone Marrow Transplant Working Group, along with members of the following committees: Non- Hodgkin's Lymphoma, Neuroblastoma, Bone Marrow Transplantation, Hodgkin's Disease, New ALL, Wilms' Tumor, Nursing, and Surgery, Radiotherapy, and Pathology Disciplines.